2200-meter band

The 2200 meter or 136 kHz band is the lowest frequency band in which amateur radio operators are allowed to transmit. It was formally allocated to amateurs at the 2007 World Radiocommunication Conference (WRC-07). The band is available on a secondary basis in all ITU regions with the limitation that amateur stations have maximum radiated power of 1 Watt effective isotropic radiated power.

The 2200 meter band is in the low frequency (LF) region, just below the 153–279 kHz longwave broadcasting band.

The International Telecommunication Union's 2007 World Radiocommunication Conference (WRC-07) in Geneva agreed a secondary allocation of 135.7–137.8 kHz to the Amateur Service on Friday, 9 November 2007. Prior to the ITU formal allocation some countries did have access or predecessors. For example, in the UK, operation on the even lower frequency of 73 kHz had been allowed from 1996 until 2003. A small number of countries also have limited license-exempt use (LowFER).

A number of European countries have already allocated the 135.7–137.8 kHz band to amateur radio use based on CEPT/ERC Recommendation 62-01 E ("Use of the band 135.7-137.8 kHz by the Amateur Service", Mainz 1997). The allocation is on a secondary basis with a maximum ERP power of 1 W. Otherwise the band 130–148.5 is allocated on a primary base to the Maritime Mobile Service and the Fixed Service. The main users are naval one-way transmissions and radiolocation systems.

Such low frequency transmissions require specialized equipment – usually custom made. In countries where it is allowed, maximum radiated power is usually limited to 1 Watt (0 dBW or 30 dBm), but even this can be extremely difficult to achieve from practical equipment and antennas. Reception also poses problems due to considerable natural and man-made noise and interference (QRN and QRM).

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